Notes & Sources

In 2017, the average income for the highest 20% of families was 3.2 times as high as that for the middle 20% ($245,040 vs. $75,840 in 2017 dollars). It was just 2.6 times as high in 1987 ($167,390 vs. $64,000).

The average income for the middle 20% of families was 4.0 times as high as that for the lowest 20% ($75,840 vs. $18,940) in 2017. It was 3.6 times as high in 1987 ($64,000 vs. $17,610).

Unlike those with higher incomes, the 20% of families with the lowest incomes have not yet reached the prerecession (inflation-adjusted) income levels of their 2007 counterparts, although they have recovered some of the income lost during the recession.

Average incomes for all quintiles fell between 2007 and 2010. Average incomes began to recover in 2011 for the top 5% and top 20% of families and later for the other quintiles. (U.S. Census Bureau, Table F-3)

The share of all income going to the 20% of families with the lowest incomes has steadily declined, from 4.6% in 1987 to 4.2% in 1997, to 4.1% in 2007, and to 3.8% in 2017. The share of income going to the top 5% of families rose from 17.2% in 1987 to 20.7% in 1997. It was 20.1% in 2007 and 20.7% in 2017. (U.S. Census Bureau, Table F-2)

Average published tuition and fees for in-state students attending public four-year colleges rose by $6,770 (in 2017 dollars) over this 30-year period—57% of the increase in income ($11,840) of the middle 20% of families and 9% of the increase in income ($77,650) of the 20% of families in the highest income bracket. (Online Table 2; calculations by the authors)